It is a radical form of recycling. Calendars from 1996 are being reused for 2024 as both are leap years that begin on a Monday.

The quirk has sparked a flurry of interest on the internet, with 1990s nostalgia fans chasing down vintage calendars nearly 30 years old.

As last year came to an end, people began posting about how the 1996 calendar works neatly in 2024, with one TikTok clip garnering over 1.5 million views.

Another viral post, this time on X (formerly Twitter), playfully reminds people to start reusing their carefully saved calendars featuring then-child star Jonathan Taylor Thomas — who is now aged 42.

The US presidential election date on a 1996 calendar is correctly marked for 2024 as November 5, and there is also the Olympics in both years — though the dates don't match up.

Second-hand sites like Ebay are selling hundreds of 1996 calendars with themes ranging from Star Wars to Barbie and Pamela Anderson.

Prices range from $50 to $200, with a Pocahontas calendar on sale for $149.99.

The calendars tap into a wave of 1990s throwback nostalgia embracing fashion trends, hairstyles and love of the "Friends" sitcom.

The Time and Date website points out you could also reuse your dog-eared calendars from 1968 and 1940.